California voters will decide in November whether to impose a one-time 5% levy on the state's billionaires, earmarked for healthcare, food assistance and education programs. The proposal, known as Proposition 40, appears on the November 3 statewide ballot and has sparked a debate over income inequality and the future of business in the nation's most populous state. A Reuters/Ipsos poll in August found 64% of independent voters nationwide support higher taxes on corporations and billionaires, while 15% oppose the idea. A UC Berkeley IGS poll in August showed 48% of likely California voters backing the measure, with 41% opposed; a September Public Policy Institute of California survey put support at 52% versus 46% opposition. Ballot measures typically lose ground as Election Day approaches, and opponents have yet to launch a major advertising push.

The initiative would tax the net worth of individuals with assets exceeding $1 billion, applying retroactively to January 1. Backers estimate the levy could generate up to $100 billion for public services, though critics argue the realistic revenue potential is closer to $40 billion. The proposal has drawn opposition from some of the state's most prominent tech figures, including Google co-founder Sergey Brin, who has contributed over $100 million to defeat the measure. Brin cited personal experience fleeing the Soviet Union under socialist rule as motivation for his stance, warning against what he sees as a path toward oppressive economic systems.

Governor Gavin Newsom, a Democrat with potential presidential ambitions, has voiced opposition to the measure, preferring instead a nationwide federal wealth tax. California holds more billionaires than any other state — over 250 individuals collectively worth more than $2 trillion, according to Forbes — and is home to major technology firms such as Apple, Meta and Nvidia. The state's history of direct democracy has produced landmark initiatives like the 1978 Proposition 13, which rolled back property taxes, though only one in three citizen proposals ultimately passes. Wealth taxes have largely disappeared from European policy landscapes in recent decades due to concerns about capital flight and economic competitiveness, but California's proposal includes safeguards to prevent evasion through relocation.

Economists studying wealth concentration note that the tax would target only the highest tier of earners while leaving middle- and upper-middle-income households largely unaffected. The measure's design seeks to capture value from assets that have appreciated significantly without triggering immediate cash outflows, potentially creating a new revenue stream for social programs without disrupting day-to-day economic activity. Whether the initiative survives the November vote remains uncertain, as undecided voters often lean toward opposition when casting ballots.